From mboxrd@z Thu Jan 1 00:00:00 1970 From: Maxime Ripard Subject: Re: [PATCH 4/8] ARM: dts: sun8i: Add touchscreen node for sun8i-a23-gt90h Date: Fri, 26 Aug 2016 22:46:37 +0200 Message-ID: <20160826204637.GC3165@lukather> References: <1470685398-14568-1-git-send-email-hdegoede@redhat.com> <1470685398-14568-4-git-send-email-hdegoede@redhat.com> <20160822183009.GX7104@lukather> <20160823092614.GF2598@lukather> <20160823151738.GM2598@lukather> <8541f3c3-c83b-bd20-42cf-03fdfb3a33d9@redhat.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="Clx92ZfkiYIKRjnr" Return-path: Content-Disposition: inline In-Reply-To: <8541f3c3-c83b-bd20-42cf-03fdfb3a33d9-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Hans de Goede Cc: Rob Herring , Chen-Yu Tsai , linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, devicetree List-Id: devicetree@vger.kernel.org --Clx92ZfkiYIKRjnr Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, Aug 23, 2016 at 05:59:50PM +0200, Hans de Goede wrote: > Hi, >=20 > On 08/23/2016 05:17 PM, Maxime Ripard wrote: > >On Tue, Aug 23, 2016 at 11:39:06AM +0200, Hans de Goede wrote: > >>Hi, > >> > >>On 23-08-16 11:26, Maxime Ripard wrote: > >>>On Mon, Aug 22, 2016 at 09:03:57PM +0200, Hans de Goede wrote: > >>>>Hi, > >>>> > >>>>On 22-08-16 20:30, Maxime Ripard wrote: > >>>>>On Mon, Aug 08, 2016 at 09:43:14PM +0200, Hans de Goede wrote: > >>>>>>The gt90h tablet has a gsl3675 touchscreen, add a dt node describin= g it. > >>>>>> > >>>>>>Signed-off-by: Hans de Goede > >>>>>>--- > >>>>>>arch/arm/boot/dts/sun8i-a23-gt90h-v4.dts | 8 ++++++++ > >>>>>>1 file changed, 8 insertions(+) > >>>>>> > >>>>>>diff --git a/arch/arm/boot/dts/sun8i-a23-gt90h-v4.dts b/arch/arm/bo= ot/dts/sun8i-a23-gt90h-v4.dts > >>>>>>index f27ebbb..da55b5a 100644 > >>>>>>--- a/arch/arm/boot/dts/sun8i-a23-gt90h-v4.dts > >>>>>>+++ b/arch/arm/boot/dts/sun8i-a23-gt90h-v4.dts > >>>>>>@@ -53,6 +53,14 @@ > >>>>>> status =3D "okay"; > >>>>>>}; > >>>>>> > >>>>>>+&gsl1680 { > >>>>>>+ compatible =3D "silead,gsl3675"; > >>>>>>+ touchscreen-fw-name =3D "silead/gsl3675-gt90h.fw"; > >>>>> > >>>>>That's not documented anywhere, and looks really suspicious. > >>>> > >>>>Ugh, that should have been in: > >>>> > >>>>Documentation/devicetree/bindings/input/touchscreen/silead_gsl1680.txt > >>>> > >>>>But somehow it is not (I believe it was there in earlier revisions of > >>>>the patch), I'll send a patch to fix this. > >>>> > >>>>About it being suspicious, this is not really firmware it is a bunch > >>>>of configuration data / lookup tables for the controller which tell > >>>>it in which order the touchscreen horizontal / vertical sensor > >>>>lines are connected to its sense pins, and what values to send > >>>>for finger x% between line z and line z+1, which differs per > >>>>tablet model, since not all tablets use the same digitizer. > >>> > >>>It's not really the firmware itself that I find suspicious, but more > >>>the encoding of a path to a file in the DT, > >> > >>It is not a path it is a filename. We could drop the "silead/" prefix > >>and put that in the driver instead to really make it a filename. > >> > >>>especially when you can > >>>apparently derive it from other informations already found in the DT > >>>(/-.fw) > >> > >>That will not work, sometimes different boards use the same digitizer > >>and thus the same firmware. Also in case of the q8 tablets, we need > >>different firmware for different variants (this is to be dealt with > >>by the q8-hardware-manager I'm working on), since although they > >>all use the same digitizer they do not wire it up to the controllers > >>pins the same in all models, so we need different firmware files > >>corresponding to different wirings. > >> > >>TL;DR: There is no 1:1 mapping between board and the firmware filename. > > > >The point still holds. It's exactly the same case than the broadcom > >nvram filename discussion, and it raised the same issues. >=20 > No it is not, in this case we also want to be able to specify > different fw names on devices using the same base dts, here > is a tablet for all the q8 tablets with gsl1680 I've: At least two other dev told you exactly that in that thread though: http://lists.infradead.org/pipermail/linux-arm-kernel/2016-June/439978.html http://lists.infradead.org/pipermail/linux-arm-kernel/2016-June/440024.html >=20 > a13-94v-0: a082 a23-tj-a23-q88-v4.0_20140815/GSL1680E_700_FW.fw 1024x600= inverted-x > a13-tzx-713b-v2.1: a082 a23-tj-a23-q88-v4.0_20140815/GSL1680E_700_FW.fw 1= 024x600 > a23-q8h-v3: a082 a23-tj-a23-q88-v4.0_20140815/GSL1688_A70_FW.fw 800x480= swapped-x-y > a23-tj-a23-q88-v4.0: a082 a23-tj-a23-q88-v4.0_20140815/GSL1680E_700_FW.fw= 1024x600 > a23-tw-ao721-v41: a082 a23-tj-a23-q88-v4.0_20140815/GSL1680E_700_FW.fw 10= 24x600 inverted-x > a23-ippo-q8h-v1.2: a082 a23-tj-a23-q88-v4.0_20140815/GSL1688_A70_FW.fw 8= 00x480 swapped-x-y > a33-ippo-q8h-v1.2: a082 a23-tj-a23-q88-v4.0_20140815/GSL1688_A70_FW.fw 8= 00x480 swapped-x-y > a33-tzx-723q4: b482 a33-Q8_V2.4_1118/GSL1680_FW_D702.fw 960x640 invert= ed-x > a33-q8-v2.4-1118: b482 a33-Q8_V2.4_1118/GSL1680_FW_D702.fw 960x640 > a33-q8h-v1.5: b482 a33-q8h-v1.5/GSL1688_A70_FW.fw 960x640 >=20 > I'm working on a q8hardware-mgr (inspired by the beagle bone cape mgr) > to automatically detect the touchscreen controller as well as the control= ler id > (the 2nd column above), and it will need to set a filename for the firmwa= re > file based on this, deriving this from the machine compatible will > simply not work here. I'm not sure why we need to stick to some insane naming scheme. Or why can't we use symlinks. Maxime --=20 Maxime Ripard, Free Electrons Embedded Linux and Kernel engineering http://free-electrons.com --Clx92ZfkiYIKRjnr Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBAgAGBQJXwKqtAAoJEBx+YmzsjxAghl8QAJ4Ld7QFUv9sKjBUr9ZpycH+ QdD58oKhGKKhyl4g88UFQzkpTUevJ4hrr/wl5MC/jtYwxYMy7qzNiLELROwUo3i5 LXIjwt6Hxnvp8lb1EyQTIQmszkK3LBHgVaBUN4FW3uRsloi/mVjRXNfA75nXD3lQ ag4IakfZFl5DRFMhc9zAJUb7SNJM8d1HcvdE5n12YtZeBZhFknd6pYqMkEgbXkFT T2l88xQAZ0LmrUExBUIbE2b6fLaMk7T4rHkpgVabRIRDx2i+02Q505FRGaiKKISJ 01sk7TRJfPfDW1VnaxNz34RO/LL0Ia9JSlZlAOgLPF3l+EOerBqv2mEhE0IJAH9d pr7srAcv6pGzc/NO5zHtTifoXD+LCcW+Gg3LOjcTSPOeZvENjvUEtrULTaMAiPzc 4BahWz5MWJxIUd/ZDndDly2XUAL3dC1+tw9XUuzlxODQpjRF9VshBZanpXSwpZM4 ig1/Di3NP+dvwV0dPSuPuRaxGBpTA6vtTe8eJ2vj4819nkZ6WIcsGwbvbWpLZh3n m2/koAWge5fc592ADTh/NDz3FoxcSYCSA0l/PnmqjhVUNINYzdKJQiHGe9meiudO cJO/JkI9lciOvEGG2WnO5zIJ9bjQ61kF1wYKH/KyVqhiGYuKfS57mhqzlQlK/nrZ 582hbwt1KTVOuwEUR2vs =tNC6 -----END PGP SIGNATURE----- --Clx92ZfkiYIKRjnr-- -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html